touch and gat causes immediate expiration

1) add an item
2) touch or gat that item with an expiration of 10 seconds
3) perform an immediate get on that item and it no longer exists

If touch or gat is run with an expiration of 0, the item properly does not expire.

Verified this failure by modifying the touch/gat/gatq unit tests to attempt to fetch the item 1 second before expiration as well as 1 second after expiration.